Trouble instaling Cerbo GX

Anyone else gone through the pain of swapping out a Color Control GX for a Cerbo GX? I've been running a Multiplus-II 48/3000 on my narrowboat for a few years now with a reasonably stable setup, and I'm seriously considering the upgrade — mostly because I want proper TouchOS access and the extra VE.Can ports.

What's bothering me is the MPPT side of things. I've got two Victron SmartSolar controllers daisy-chained via VE.Direct and I'm not entirely sure whether I need to start thinking about VE.Can adapters or if the direct connections just map across cleanly. The Victron docs are their usual brand of technically complete but practically useless.

Few things I actually want to know before I pull the trigger:

• Did anyone have issues with ESS or AC coupling settings getting wiped or scrambled during the swap?
• Do the existing VEConfigure profiles carry over, or do you have to reconfigure from scratch in VictronConnect?
• Any weirdness with BMS comms? I'm on Fogstar Drift cells with a Daly BMS — not the most sophisticated setup admittedly

I've read about people having to do firmware updates in a specific order to avoid the system throwing faults, but I can't find a definitive answer on what that order actually is.

It shouldn't be this complicated to swap one bit of Victron kit for another bit of Victron kit. Is it actually straightforward in practice, or am I right to be nervous about it?

@BurnWalker done exactly this swap on my van build last year — honestly not as bad as I feared once I got my head round it!

Few things that tripped me up:

• VE.Can termination — make sure you've got the 120Ω terminator on the open end of the bus, easy to overlook
• The Cerbo needs the GX Touch 50 mounted separately if you want a screen (unlike the CCGX which is all-in-one)
• Worth doing a firmware update via VRM straight after first boot before you change any settings

The Victron Connect app makes the whole thing much less stressful than messing with cables blind. Also double-check your VE.Direct cables are properly seated — mine gave phantom comms errors for days before I reseated them properly.

What's the specific issue you're hitting? Happy to dig into it 👍

@BurnWalker did you remember to update the Multiplus-II firmware before swapping the GX unit? Caught me out on my garden office setup — the Cerbo basically threw a tantrum because the old firmware on the inverter wasn't speaking the right VE.Bus dialect. Spent an embarrassing amount of time staring at a blinking LED wondering what I'd done wrong.

Also worth double-checking: are you using a VE.Bus cable or going straight USB? Some folk assume USB is fine but you really want the proper VE.Bus connection for full comms.

What's your current firmware showing on the Multiplus? And is the Cerbo at least detecting it, just not communicating properly — or is it acting like the inverter doesn't exist at all? That'll narrow it down considerably.

@BurnWalker oh this brings back memories! I did something similar when I upgraded my static caravan setup — not a narrowboat, but the Cerbo threw me completely because I'd assumed it was a straight swap and it absolutely isn't 😅

One thing nobody mentioned to me at the time: double-check your VE.Bus cable is seated properly on the Cerbo. Mine looked fine but wasn't quite clicked home, and I spent an embarrassing amount of time convinced the unit was faulty. The Multiplus-II just sat there looking confused.

Also worth knowing — the Cerbo's WiFi and Bluetooth are genuinely brilliant once you're through the setup pain. Being able to monitor everything remotely has been a game-changer for my emergency backup situation, especially checking in when I'm away from the caravan.

What firmware version are you running on the Multiplus currently?

@BurnWalker one thing that tripped me up when I did a similar swap on my shepherd's hut build — the VE.Can termination resistors. If you've got anything daisy-chained on that bus, both ends must be terminated or the Cerbo just throws a fit and won't see half your devices.

Grab the VictronConnect app and check the Device List straight after boot. If something's missing that was visible on the old CCGX, nine times out of ten it's a termination or address conflict rather than a wiring fault.

Also worth checking: the Cerbo's DVCC settings don't always mirror across automatically from the old unit, so double-check your charge current limits before you let it run unattended overnight.

@BurnWalker ooh I'm watching this thread closely — I've been thinking about adding a Cerbo GX to my garden office setup for ages but keep putting it off precisely because of faff like this.

Quick question nobody's asked yet — did you have any VRM portal issues after the swap? I'm wondering whether the old CCGX installation ID carries over or whether you end up with a ghost system sitting in your VRM account alongside the new one. That would do my head in.

Also, were you running any MPPT controllers on VE.Direct? I've got a couple of Victron SmartSolars and I'm curious whether those reconnected cleanly or needed fiddling with.

@QuietMaker's point about VE.Can termination is a good shout — caught a mate out on his motorhome build last year, completely avoidable headache.